Are there any hydroplane owners here?

John, there are several sites out there, although I can't find them in my favorites anymore. Try the APBA. There are people in the Mass. area that still race and come to Maine every spring to Watchic Lake in Standish. There's always boats for sale. I bet if you do a google search for hydroplane racing you'll come up with a lot. From what I've seen, a lot of the kits you see aren't the real race boats, although the one you linked is. I had a Marchetti C Hydro with a Mach 30 racing engine years ago that was a real race boat. That is definitely one of things I've owned that I wish I never sold. One of the racers back then that I bought the engine from was Clark Maloof. If you google his name, you'll find some forums. I believe he still builds boats. Like everything else, buying something used is a better value than buying or building all new.

Poor picture, but this was mine

DrCC wrote: My only experience was with the 8 footers.   3-point and the mini-max. Half the fun IS the building.

I'd say that too if I had your skills.
I don't believe the Jupiter or Wetback are competitive race boats any more, but they are classics IMO. Who knows, one could end up as a decoration at the shack up north. Billy, those with fewer skills get their enjoyment from polishing them as opposed to building them.

Riley wrote: Hydroracer.com Google Clark Maloof and a lot of hydro stuff comes up. A regular outboard engine will not fit on one of those boats. There designed for a short racing low unit.

I understand that these were not designed for "pleasure/fishing outboards. A Merc 20H or KG7 or KG9 would suit if you want to go fast. I have seen several that have been built for fun rather than going really fast. Some owners fit them with pleasure motors and the transom is a bit taller for this? I saw one that had the standard LU on it so it had FNR and a traditional Mercontrol. I understand you will never get the speed of a KG9 or 20H out of them but they should go pretty well and be a toy for an old fart.This is on the Clark Craft site about the Jupiter:
Although Jupiter is an "out and out" racing hydro, it will take any pleasure motor from 7 hp up ... The weight of the motor rather than the hp will determine the motor to use 110 pounds is about the limit.

Jupiter with standard Merc 200, electric start, and Mercontrol
Jupiter with Johnson 25

Riley wrote: Those boats go right along with those engines. Having neutral, let alone reverse would be a great plus! And the exhaust won't annoy everyone on the lake.

Not to mention electric start. 3 surgeries on one shoulder and one on the other have made it unpleasant to pull a starter rope at best. A new LI-ON battery puts out 420CCA and weighs under 4lbs. Makes electric start an option over old flooded lead acid batteries.

still funny though